Coupe panoramic sunroof - buzz above 80 km/h
Thread Starter
MBWorld Fanatic!
Joined: Dec 2003
Posts: 3,275
Likes: 236
From: BC, Canada
2003 C230K Coupe Orion Blue
Coupe panoramic sunroof - buzz above 80 km/h
I can't figure this out for the life of me. I replaced the driver's support arm (the thing that pops up and holds up the deflector when the panoramic roof opens) when it exploded on me a few months ago. Everything works fine until I go above 80 km/h, then there's a buzzing noise. This is not to be confused with the wind "thump thump thump" noise, which is easily mitigated by cracking open a window. This is a distinctly different buzz. Almost sounds like a bee.
When I touch the driver's side support arm above 80km/h, I can physically feel it vibrating (this is the source of the noise). However, it stops buzzingi if if I gently (less than the weight of an apple) push downwards on the passenger side arm. The driver's side requires a much more forceful push downwards before it stops vibrating. I thought maybe the new driver's strut was a dud, but the noise wouldn't go away even after I reinstalled the old driver's strut.
I've tried greasing both mechanisms on both the spring and pin ends with plenty of lithium grease. No dice.
Any ideas on what to try next?
On a side note, I managed to lose one of the circlips (e-clip) while performing this repair. MB only sells that circlip as part of a kit (which includes a screw and the stainless steel pin) for $76.
Anyone know a cheaper place to get a replacement. Also, what size is it? It looks like 3mm but I can't be sure, as I'm not sure I'm measuring this thing properly.
When I touch the driver's side support arm above 80km/h, I can physically feel it vibrating (this is the source of the noise). However, it stops buzzingi if if I gently (less than the weight of an apple) push downwards on the passenger side arm. The driver's side requires a much more forceful push downwards before it stops vibrating. I thought maybe the new driver's strut was a dud, but the noise wouldn't go away even after I reinstalled the old driver's strut.
I've tried greasing both mechanisms on both the spring and pin ends with plenty of lithium grease. No dice.
Any ideas on what to try next?
On a side note, I managed to lose one of the circlips (e-clip) while performing this repair. MB only sells that circlip as part of a kit (which includes a screw and the stainless steel pin) for $76.
Anyone know a cheaper place to get a replacement. Also, what size is it? It looks like 3mm but I can't be sure, as I'm not sure I'm measuring this thing properly.
Last edited by slammer111; Aug 19, 2015 at 03:50 AM.
Thread Starter
MBWorld Fanatic!
Joined: Dec 2003
Posts: 3,275
Likes: 236
From: BC, Canada
2003 C230K Coupe Orion Blue
Not quite sure what you mean. The driver's support arm broke, and I had it replaced with an OEM one from the dealer. Everything else worked fine at the time - 2 hinges where the deflector attaches, and the passenger side support arm.
The circlip is a separate problem. The reason I lost it was because I was taking this thing apart 10 times while trying to diagnose the buzzing noise.
The circlip is a separate problem. The reason I lost it was because I was taking this thing apart 10 times while trying to diagnose the buzzing noise.
Last edited by slammer111; Aug 19, 2015 at 11:20 AM.
